Lithium-Silicon Nanowire Batteries To Hold 10X Juice

Lithium batteries made with silicon nanowires hold ten times the charge that current ones do, and scientists are speculating that this may be sufficient to keep a Windows Vista laptop running until lunchtime.

From ScienceDaily:

"The electrical storage capacity of a Li-ion battery is limited by how much lithium can be held in the battery's anode, which is typically made of carbon. Silicon has a much higher capacity than carbon, but also has a drawback.

Silicon placed in a battery swells as it absorbs positively charged lithium atoms during charging, then shrinks during use (i.e., when playing your iPod) as the lithium is drawn out of the silicon. This expand/shrink cycle typically causes the silicon (often in the form of particles or a thin film) to pulverize, degrading the performance of the battery.

Cui's battery gets around this problem with nanotechnology. The lithium is stored in a forest of tiny silicon nanowires, each with a diameter one-thousandth the thickness of a sheet of paper. The nanowires inflate four times their normal size as they soak up lithium.
But, unlike other silicon shapes, they do not fracture."

We've been hearing this kind of "20 hour battery" talk from the fuel cell people for years, now, so forgive us a few jaded notes. But silicon is like totally the coolest element on the periodic table with an atomic weight lower than 100, so we'll give
Prof. Yi Cui and co. the benefit of the doubt.

New Nanowire Battery Holds 10 Times The Charge Of Existing Ones [Science Daily via Sean Bradshaw]